I had that same block for a long time. First it was 7, then 8, then 9, then 10. When I shot my 300 I wasn't so concerned about the 12th ball as I was that 11th. I knew that if I didn't blow that 11th ball (for the 5th time), I knew I was golden, and I was.
The only thing I did different during my 300 than previous times was to not think about it being the 10th frame of a 300, but just make it like it was the 1st frame over and over. I didn't focus on making a "good shot", just to revert back to the fundamentals of hitting my target and keeping a fluid armswing.
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Brian Longo
25+ years bowling, 8 years "behind the counter"
as a mechanic, "laneman" and in the pro shop
--"Even the expert was once a beginner"--
--"There are no magical balls, just magical bowlers"--